What term describes a joint that allows rotational movement?

The term that describes a joint allowing rotational movement is the pivot joint. This type of joint features a rounded or pointed surface of one bone that fits into a ring formed by another bone, allowing for rotation around a central axis. A classic example of a pivot joint is the atlantoaxial joint located between the first and second cervical vertebrae, which enables the head to turn from side to side.

In contrast, other joint types have different mobility characteristics. A ball-and-socket joint, such as the hip or shoulder, permits a wide range of movements, including rotation, but is primarily defined by its ability to move in multiple axes. Hinge joints, like the elbow and knee, are limited to flexion and extension, allowing movement in a single plane. Ellipsoidal joints permit movement in two axes, such as the wrist, but do not primarily allow for rotational movement as pivot joints do. Understanding these differences in joint types is crucial for grasping human biomechanics and movement.